Matsuro, R., et al., Chemistry of Materials 15, 3-5 (2003) have prepared a nitroxide based living radical polymerization initiator having a phosphoric acid moiety and used it to interact with magnetic nanoparticles; polymerization in the presence of styrene yielded nanoparticles of polystyrene grafted magnetite; in this case, the living radical polymerization initiator is not attached to the nanoparticles. Skaff, H., et al., Journal of the American Chemical Society 124, 5729-5733 (2002) has employed functional phosphine oxide as ligand for attachment to CdSe nanoparticles and used the combination to support the polymerization of cyclic olefins radially outward from the surfaces by ruthenium-catalyzed ring-opening metathesis polymerization (ROMP); in this case there is no living free radical polymerization but rather metathesis polymerization. The same group has recently reported (Sill, K., et al., Chemistry of Materials 16, 1240-1243 (2004)) the use of nitroxide-mediated controlled free radical polymerization by attachment of phosphine oxide functional alkoxyamine initiator directly from the surface of CdSe nanoparticles to prepare dispersed polymer-nanoparticle composite materials; this differs from the invention in that the initiator is different.
Heretofore there has been no other report of formation of free radical living polymerization initiators attached to nanoclusters and use thereof to form oxide or quantum dot star polymers or copolymers.